PROBLEM TO BE SOLVED: To provide a processor device for supporting diagnosis of a lesioned part based on a blood vessel and a gland duct, an endoscope system, a method for operating a processor device, and a program.SOLUTION: An RGB image signal obtained by imaging an observation object is acquired. A blood vessel is extracted from a B image signal in the RGB image signal to generate a blood vessel image signal. A gland duct is extracted from the B image signal in the RGB image signal to generate a gland duct image signal. A blood vessel index is calculated from the blood vessel image signal, and a gland duct index is calculated from the gland duct image signal. The blood vessel index and the gland duct index are used to generate a special image for display including the blood vessel index and the gland duct index 79 as well as the observation object 78.SELECTED DRAWING: Figure 8
